Percutaneous circulatory support device facilitating reduced hemolysis

Abstract

A percutaneous circulatory support device includes an impeller housing and a primary impeller disposed within the impeller housing. The primary impeller is rotatable relative to the impeller housing to cause blood to flow through the percutaneous circulatory support device. The device further includes a counter impeller disposed within the impeller housing.

We claim: 
     
         1 . A percutaneous circulatory support device, comprising:
 an impeller housing comprising a proximal end portion;   a primary impeller disposed within the impeller housing, the primary impeller being rotatable relative to the impeller housing to cause blood to flow through the percutaneous circulatory support device; and   a counter impeller disposed within the impeller housing, the counter impeller being rotatable relative to the impeller housing to create a turbulent barrier and thereby cause blood to flow away from the proximal end portion of the housing.   
     
     
         2 . The percutaneous circulatory support device of  claim 1 , further comprising a motor operatively coupled to the primary impeller and rotating the primary impeller relative to the impeller housing to cause blood to flow through the percutaneous circulatory support device. 
     
     
         3 . The percutaneous circulatory support device of  claim 2 , wherein the motor is further operatively coupled to the counter impeller, the motor rotating the primary impeller and the counter impeller together relative to the impeller housing. 
     
     
         4 . The percutaneous circulatory support device of  claim 3 , further comprising an impeller shaft being fixed relative to the primary impeller and the counter impeller. 
     
     
         5 . The percutaneous circulatory support device of  claim 3 , further comprising a driving magnet operatively coupled to the motor and a driven magnet operatively coupled to the driving magnet, and the motor rotates the primary impeller and the counter impeller together, via the driving magnet and the driven magnet, relative to the impeller housing. 
     
     
         6 . The percutaneous circulatory support device of  claim 5 , wherein the counter impeller is disposed between the primary impeller and the driven magnet. 
     
     
         7 . The percutaneous circulatory support device of  claim 5 , wherein the driven magnet is disposed in the proximal end portion of the impeller housing. 
     
     
         8 . The percutaneous circulatory support device of  claim 1 , wherein the primary impeller comprises a first number of impeller blades and the counter impeller comprises a second number of impeller blades, the second number of impeller blades being greater than the first number of impeller blades. 
     
     
         9 . The percutaneous circulatory support device of  claim 1 , wherein the primary impeller comprises a plurality of first impeller blades and the counter impeller comprises a plurality of second impeller blades, the second impeller blades having the opposite pitch than the first impeller blades. 
     
     
         10 . The percutaneous circulatory support device of  claim 1 , wherein the impeller housing further comprises an outlet, and the outlet extends both proximally and distally beyond the counter impeller. 
     
     
         11 . The percutaneous circulatory support device of  claim 1 , wherein the primary impeller has a first axial length, the counter impeller has a second axial length, and the second axial length is less than the first axial length. 
     
     
         12 . A percutaneous circulatory support device, comprising:
 an impeller housing comprising a proximal end portion;   a first impeller disposed within the impeller housing, the first impeller being rotatable relative to the impeller housing to cause blood to flow through the percutaneous circulatory support device; and   a second impeller disposed within the impeller housing, the second impeller being rotatable relative to the impeller housing to create a turbulent barrier and thereby cause blood to flow away from the proximal end portion of the housing.   
     
     
         13 . The percutaneous circulatory support device of  claim 12 , further comprising a motor operatively coupled to the first impeller and rotating the first impeller relative to the impeller housing to cause blood to flow through the percutaneous circulatory support device. 
     
     
         14 . The percutaneous circulatory support device of  claim 13 , wherein the motor is further operatively coupled to the second impeller, the motor rotating the first impeller and the second impeller together relative to the impeller housing. 
     
     
         15 . The percutaneous circulatory support device of  claim 14 , further comprising a driving magnet operatively coupled to the motor and a driven magnet operatively coupled to the driving magnet, and the motor rotates the first impeller and the second impeller together, via the driving magnet and the driven magnet, relative to the impeller housing. 
     
     
         16 . The percutaneous circulatory support device of  claim 15 , further comprising an impeller shaft being fixed relative to the first impeller and the second impeller. 
     
     
         17 . A method for using a percutaneous circulatory support device, comprising:
 positioning the percutaneous circulatory support device at a target location within a patient;   rotating a primary impeller of the percutaneous circulatory support device to cause blood to flow through the percutaneous circulatory support device; and   rotating a counter impeller of the percutaneous circulatory support device to create a turbulent barrier and thereby cause blood to flow away from a proximal end portion of a housing of the percutaneous circulatory support device.   
     
     
         18 . The method of  claim 17 , wherein rotating the primary impeller and rotating the counter impeller comprise rotating the primary impeller and the counter impeller together relative to the housing. 
     
     
         19 . The method of  claim 18 , wherein the percutaneous circulatory support device further comprises a motor operatively coupled to the primary impeller and the counter impeller, and rotating the primary impeller and the counter impeller together relative to the housing comprises driving the primary impeller and the counter impeller via the motor. 
     
     
         20 . The method of  claim 19 , wherein the percutaneous circulatory support device further comprises a driving magnet operatively coupled to the motor and a driven magnet operatively coupled to the driving magnet, and driving the primary impeller and the counter impeller via the motor comprises driving the first impeller and the second impeller together, via the motor, the driving magnet, and the driven magnet, relative to the housing.